1. Field of the Invention
The invention relates to a rolling bearing, a machine element, and a solid-film formation method.
2. Description of the Related Art
When a rolling bearing is used in a vacuum environment or a corrosive environment in which the use of grease or oil is precluded, bearing components such as an inner ring and an outer ring are provided with a film-like coating formed of a solid lubricant. The coating is conventionally formed of for example, soft metal such as gold, silver, or lead, or a layer structure material such as graphite or molybdenum disulfide.
When the rolling bearing is provided with the coating formed of the solid lubricant, a slight amount of solid lubricant peels off during rotation of the bearing to contribute to lubrication. The use of the coating reduces the number of dust particles from the rolling bearing compared to the use of grease or oil. Nevertheless, in an environment that needs high cleanliness, the application of the coating poses a problem. Thus, a rolling bearing has been proposed in which bearing components are provided with a solid film of a fluorine-containing polyurethane polymer compound (for example, Japanese Patent Application Publication No. H9-137830 (JP H9-137830 A)).
The technique described in JP H9-137830 A provides a bearing that is suitable in a vacuum environment, a corrosive environment, and a clean environment in which the use of grease or oil is precluded.